Journal of High Energy Physics

, 2014:43 | Cite as

Effects of color reconnection on \( t\overline{t} \) final states at the LHC

  • Spyros Argyropoulos
  • Torbjörn Sjöstrand
Open Access
Regular Article - Theoretical Physics


The modeling of color reconnection has become one of the dominant sources of systematic uncertainty in the top mass determination at hadron colliders. The uncertainty on the top mass due to color reconnection is conventionally estimated by taking the difference in the predictions of a model with and a model without color reconnection. We show that this procedure underestimates the uncertainty when applied to the existing models in Pythia 8. We introduce two new classes of color reconnection models, each containing several variants, which encompass a variety of scenarios that could be realized in nature and we study how they affect the reconstruction of the top mass. After tuning the new models to existing LHC data, the remaining spread of predictions is used to derive a more realistic uncertainty for the top mass, which is found to be around 500 MeV. We also propose how future LHC measurements with \( t\overline{t} \) events can be used to further constrain these models and reduce the associated modeling uncertainty.


QCD Phenomenology Monte Carlo Simulations 


Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.


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Copyright information

© The Author(s) 2014

Authors and Affiliations

  1. 1.Department of Astronomy and Theoretical PhysicsLund UniversityLundSweden
  2. 2.Deutsches Elektronen SynchrotronHamburgGermany

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